The Modal Assurance Criterion (MAC) is a modal indicator designed to decide whether the mode shapes used in its computation are corresponding same mode. During structural monitoring, it can be applied evaluate changes shapes. When estimated from measurement data, MAC inherits their statistical properties, thus afflicted with uncertainty. evaluation of this uncertainty particularly relevant when...

Recently the superior performance of the PolyMAX modal parameter estimation method using frequency response functions was demonstrated. The method can be implemented in a very similar way as the industry standard polyreference (time-domain) least-squares complex exponential method: in a first step a stabilisation diagram is constructed containing frequency, damping and participation information...

It has been observed that even though modal frequencies are well estimated using Operational Modal Analysis (OMA) techniques, damping estimation is not as accurate. The opinions on this aspect of OMA have been widely varying and no consensus or definite answers are available. In this paper the OMA procedure, data processing and modal parameter estimation, is studied with respect to proper dampi...

Operational Modal Analysis, also known as Output Only Modal Analysis, has in the recent years, been used for determination of modal parameters of civil engineering structures and is now becoming widely used also for mechanical structures. The advantage of the method is that no artificial excitation needs to be applied to the structure, or force signals to be measured. In this paper, the non-par...